The build-up to the new NBA season has been dominated by the debate over whether players should be vaccinated against coronavirus.

NBA legends Michael Jordan and Kareem Abdul-Jabbar have backed the league’s stance. Even Spain’s prime minister Pedro Sanchez had his say on the matter in parliament.

With the 2021-22 season set to tip off on Tuesday, the vaccination rate among NBA players is about 95% and the debate has centred on one man – Kyrie Irving.

Because of local vaccine rules, the Brooklyn Nets star cannot play or practise with the team in New York until he has had at least one shot, ruling him out of home games.

Now the Nets have ruled him out altogether, meaning the NBA returns with one of its biggest stars sidelined indefinitely, and sacrificing about $15.6m (£11.5m).z

What happened with Kyrie Irving?

Since coming into the league as the number one draft pick in 2011, Irving has not just won a championship with the Cleveland Cavaliers (2016), he’s become an activist, a philanthropist and one of six vice-presidents of the National Basketball Players Association (NBPA).

The 29-year-old, who is of African American and Native American heritage, also admits to becoming a “big conspiracy theorist”.

He once apologised for saying the earth is flat and this year has been sharing microchip claims about the Moderna vaccine on social media.

Mandates for all NBA team staff, coaches and referees to be vaccinated have been passed, but the NBPA is refusing to accept one for the players.

However, last month New York and San Francisco passed local vaccine mandates for all those entering indoor entertainment and performing arts venues. This month, Los Angeles followed suit.

Those markets feature five NBA teams, including Brooklyn, so Irving was set to miss home games. He was going to be hit in the pocket too.

The NBPA did agree to a reduction in pay of about 1% of an unvaccinated player’s salary for each game they miss. For Irving, that’s about $380,000 (£279,000), and with 41 home games in the regular season, that would total about $15.6m (£11.5m) for the whole season.

Speculation turned to how the Nets, expected to be championship-contenders after recruiting the star trio of Irving, Kevin Durant and James Harden, would manage having their starting point guard as a part-time player.

They reacted by saying the seven-time All-Star won’t be selected at all “until he is eligible to be a full participant”. In the same statement, Brooklyn’s general manager Sean Marks added: “Kyrie has made a personal choice and we respect his individual right to choose.”

Why are some NBA players still unvaccinated?

Speaking on Instagram Live on Wednesday, Irving said: “Do what’s best for you, but I am not an advocate for either side. I am doing what’s best for me.

“I know the consequences here, and if it means that I’m judged and demonised for that, that’s just what it is, that’s the role I play.”

Andrew Wiggins was another of the vaccine ‘holdouts’ subject to local vaccine mandates as his team, the Golden State Warriors, are based in San Francisco.

The 26-year-old had a request for a religious exemption rejected by the NBA. A week later Wiggins had the jab but said he felt “forced to”, adding: “It was a tough decision. Hopefully, it works out in the long run and in 10 years I’m still healthy.”

Washington Wizards’ three-time All-Star Bradley Beal has said he is unvaccinated for “personal reasons”, adding: “You can still get Covid and still pass it along if vaccinated, so…”

The following day the 28-year-old said he was “still considering getting the vaccine. I’m not sitting up here advocating that you shouldn’t get it”.

The Denver Nuggets’ Michael Porter Jr said “there’s a chance you could have a bad reaction to the vaccine, I don’t feel comfortable”, while Orlando Magic’s Jonathan Isaac said he is “not anti-vax” and referred to natural immunity. He, Porter and Beal have all recovered from bouts of coronavirus.

“I’m not ashamed to say that I’m uncomfortable with taking the vaccine at this time,” said Isaac, 24.

“I understand that the vaccine would help if you have Covid, you’ll be able to have less symptoms from contracting it. But with me having Covid in the past and having antibodies, with my current age group and physical fitness level, it’s not necessarily a fear of mine.”

What else has been said?

New York City mayor Bill de Blasio has told Irving to “get vaccinated. Your fans want to see you, we all want you back”, while Donald Trump Jr tweeted that Irving had “just sacrificed more than [Colin] Kaepernick ever did!”

Another Republican, Texas senator Ted Cruz, tweeted that he “stands with Kyrie Irving” and the NBA’s other unvaccinated players.

Michael Jordan said that he’s a “firm believer in science” and is in “total unison with the league”. Fellow Hall of Famer Abdul-Jabbar was part of an information campaign by the NBA, encouraging Americans to get vaccinated.

The six-time NBA champion also told Rolling Stone: “There is no room for players who are willing to risk the health and lives of their team-mates, the staff and the fans simply because they are unable to grasp the seriousness of the situation or do the necessary research.”

After initial hesitancy, Los Angeles Lakers star James said he researched the vaccine before deciding “it was best suited for me and my family and my friends. But as far as speaking for everybody and what they want to do, that’s not my job.”

Giannis Antetokounmpo, last season’s Finals MVP as the Milwaukee Bucks won the NBA title, has also confirmed he’s been vaccinated, saying: “I did what was best for me and my family to stay protected.”

What are the rules for unvaccinated players?

After training camps started, the vaccination rate among NBA players rose from 90% to 95%, leaving about 30 still to get the jab across the league’s 30 teams. That compares to 64.7% for the whole of the US population.

Visiting players are exempt from the local vaccine mandates so any still unvaccinated can play away games in New York, San Francisco or LA.

However, according to NBA protocols, they must have daily testing before entering a team facility or interacting with players and coaches. Vaccinated players are only tested if they show symptoms or are a close contact of a positive case.

Unvaccinated players could even be given jail time when visiting Canada to play the Toronto Raptors.

According to Canada’s Quarantine Act, they must take a Covid test when arriving in the country and will only be permitted to leave their hotel room for team activities. Anyone breaking the rules can face up to six months in prison and/or $750,000 (£443,275) in fines.

As for Irving, while he’ll still be paid for Brooklyn’s games on the road this season, he’ll forfeit his salary for home games. He could also have missed out on a contract extension worth $186m (£136m).

The Nets may now look to trade him, but how will rival teams feel about his vaccination status? Irving insists he won’t be retiring though.

“I’m not leaving this game like this,” he said. “There’s still so much more work to do.”